Earth boring device



Oct. 1, 1935. c, E. BANNISTER EARTH BORING DEVICE Filed Feb. 17, 1934 6 Sheets-Sheet l 1 jzvezzlor d 6:

Oct. 1, 1935. c BANMSTER 2,016,068

EARTH BORING DEVICE iii-j Oct; 1, 1935. c BANNlsTER 2,016,068

EARTH BORING DEVICE 1 443 'I 1 22%)" J ld2ww 1935- c. E. BANBIISTER H 2,016,068 I EARTH BORING DEVICE I l Filed Feb. 17, 1934 h e Sheets-Shet 5 Oct. 1, 1935. c. E. BANNISTER I 2,015,068

' EARTH BORING DEVICE Filed Feb. 17, 1934 Y 6 Sheets-Sheet 6 ?z@mmdd% Aug. /7. I by s 7 Patented Dot. 1,- 1935 UNITED STATES PATENT QFFICE 2,016,068 EARTH BORING DEVICE Clyde E. Bannister, Akron, Ohio Application February 17, 1934, Serial No. 711,713

16 Claims.

More specific objects are to provide conveniently and economically for drilling a deep hole without successive reductions of diameter such as are necessary in the case of apparatus heretofore used; to provide for conveniently and economical drilling a downward extension of a hole with a diameter equal to or greater than the diameter of the hole farther up or of a casing therein; and to provide for the progressive placing of a casing in a hole drilled by the hydraulic method without substantial interruption of the drilling operation.

The present application is a continuation in part of my application Serial No. 589,885, filed January 30, 1932.

The machine of the preferred embodiment shown in the accompanying drawings comprises a central motor-and-bit assembly of the oscillating type, a set of planetary or out-rigger motor-and-bit assemblies which are compelled to oscillate as a unit with the motor-casing of the central assembly while the out-rigger bits are oscillated on their individual axes by their respective motors, and an inertia member having lost-motion connection with the shaft of the central bit and through the central-motor shell, with the out-rigger assembly so that reaction of the motive fluid of the central motor will be sustained in part by the inertia member if in the relative oscillation of the central assembly and the out-rigger assembly the oscillation of either becomes too great in amplitude at the expense of the others corresponding reduction of amplitude, the inertia member thus compelling a proper amplitude of oscillation for both assemblies.

Of the accompanying drawings:

Fig. 1 is a cross-section of the formation at the position of a hole being drilled, showing in side elevation apparatusembodying my invention in its preferred form.

. Fig. 2 is a cross-section on line 2-2 of Fig. 4.

Fig. 3 is a bottom plan view of the apparatus. Fig. 4 is a section of parts of the apparatus showing in elevation the motor-and-bit assembly I in expended condition.

Fig. 5 is a similar view showing the motor-andbit assembly in retracted condition.

Fig. 6 is a section of parts of the apparatus in the region of the central bit.

Fig. 6 is a section of the parts next above those of Fig. 6 I

Fig. 6 is a section of the parts next above those of Fig. 6

Fig. 7'is a section on line of Fig. 6 .5.

Fig. 8 is a section of parts of the apparatus as viewed obliquely from the left of Fig. 6

Fig. 9 is a section on line 99 of Fig. 6

Fig. 10 is a section on line Ill-40 of Fig. 6

Fig. 11 is a section of .parts of the apparatus 10.

shown in Figs. 6 and 6? showing the valve arrangement of one of the motors.

Fig. 17 is a vertical section of one of the motors preferably used for driving a set of outrigger or planetary bits.

Fig. 18 is a section on line Ill-l8 of Fig. 17. Fig. 19 is a section on line I9l9 of Fig. 17 Fig. 20 is a side elevation of parts of the valve assembly of Figs. 14, 15, 17 and 19.

Fig. 21 is a section on line 2l2l of Fig. 17. 25

Fig. 22 is a section on line 2222 of Fig. 17.

Referring to the drawings, I designates a central barrel or casing having therein a central shaft 2I0 on the lower end of which is mounted a central cutting bit or boring tool 2, the casing and shaft being parts of a fluid pressure motor adapted to effect oscillation of the bit 2 with relation to the barrel I.

For illustrative purposes I have shown, for the driving of this central bit, a motor of the type illustrated in my prior and copending application Serial No. 271,923, filed April 21, 1928.

In the preferred form of the device, the action of the motor contained in the barrel I will elfect movement of the central bit with relation to said barrel, preferably an oscillatory movement. The description of the motor in the barrel I will be set forth hereinafter, after a description of theomotors for the planetary barrels.

Circumferentially arranged with respect to the shaft M0 is rotatably mounted in the plugs or blocks 6 and 8, and has associated therewith an impeller or vane III, this impeller being preferably formed integral with the shaft III. The plugs 6 and 8 are cut away on their top and bottom faces. respectively, and seated in said cutaway portions are the flanges I2 (Figs. 19, 21 and 22) of members I3 and I4, screws I5 securing said flanges I2 to the plugs 6 and 8 respectively.

' The plugs 6 and 8, barrel II, and the members I3 and I4 define a chamber I6 within which the impeller III may oscillate.

The member I3 is provided with an inlet port I! and with an exhaust port I8 communicating with the chamber I6, and the member I4 is provided with an inlet port I9 and an exhaust port 20 likewise communicating with the chamber I6 (Fig. 19). The members I3 and I4 are covered, throughout the major portion of their exposed surfaces with rubber coatings secured thereto, and these rubber coatings form seats 2I on the inlet port I1, 22 on the exhaust port I8, 23 on the inlet port I9, and 24 on the exhaust port 20; It will be noted thatthe pair of seats 2| and 22 and the pair of seats 23 and 24 are approximately in parallel planes.

The shaft I and impeller III are also coated with rubber, as clearly indicated at 25 in Figs. 14, 15 and 17, lips 26, 26 (Figs. 14 and 15) being formed in the rubber coating on the impeller and bearing against the wall of the chamber I6 to effect a tight joint.

Fixed to the plug Ii -by a-pin 21 is a collar 28,

said collar surrounding the shaft I6 and being provided with a recess or cut-away portion 29 to permit the fluid conducted through the interior 9 of the working barrel I I to-flow around the upper end of the shaft I0 and down around said shaft to constitute a lubricant.

Each of the plugs 6 and 8 is cut away as indicated at 30 to permit uninterrupted passage of the fluid through all of the ports I'I, I8, I9 and 26.

Each of the members I3 and I4 is provided with a recess 3|, and in these recesses is seated the hub 32 of a double-wing valve 33, this valve having a pivot pin 34 therethrough adjacent to the: lower part of the hub 32. The pivot 34 is provided with a knife edge 35 on its upper surface, said knife edge being engaged by a bushing 36 with the same held to the members I3 and I4 by pins 31, and in a bushing 38 which is likewise held against rotation in the members I3 and I4 by a pin 39.

The wings of the valve 33 extend above and below the pivot 34, and are provided with a face 40 adapted to seat against the port seat 2 I, a face 4I adapted to seat against the port seat 23, a face 42 adapted to seat against the port seat 22, and with a face 43 adapted to seat against the port seat 24. The valve 33 is so constructed and arranged as to close an alternate inlet and exhaust port simultaneously, as for example the inlet port I! and outlet port 20, with the valve in the position illustrated in Fig. 19.

Assuming that the valve 33 is in the position illustrated in Fig. 19, it will be apparent that fluid being forced through the interior 9 of the barrel H will pass through the inlet port I9 into the chamber I6, bearing against and forcing the impeller III in a clockwise direction, toward the position illustrated in dotted lines at 44 in Fig. 14. This will effect an exhaust or discharge of the fluid on the opposite side of the impeller I II out through the exhaust port I8, whence it will continue downwardly through the barrel and to the bit, as will be more fully described hereafter.

This movement of the impeller I II will effect a rotative movement of the shaft II), and of the clutch block 45 (Figs. 1'7 and 18) which is keyed thereto by a key 46, a set screw 41 being utilized as an additional securing element. The block 45 is recessed on each side, as illustrated at 48 in Fig. 18, and projecting upwardly into the recesses 48 are reduced extensions 49, 49 of a sleeve 58, said sleeve 58 being provided with apertures 5| to permit the passage of fluid to the interior of said sleeve, said sleeve also being provided with a spider 52 in which is seated the lower reduced end of the shaft I6, the shaft III being threaded at 53 and lock nuts 54 preventing longitudinal displacement of the block 45, the lower nut 54 being pinned at 55. The sleeve 50 is also provided with a plurality of radially projecting flanges 56, said flanges interengaging recesses 51 in a split bushing 56, the

, sleeve and its flanges being provided with a rubber coating as clearly illustrated. The split bushing 58 is confined between two threaded plugs 59 and 60 threaded into the lower end of the bottom section of the barrel. Secured to the bottom oi the sleeve 50 is a bit or cutting tool 6 I, which may be of any desired size or shape, so long as it is provided with cutting edges 62 adapted to cut with equal efficiency in either direction of oscillation of All of the rubber surfaces herein described, on rotating or oscillating parts, are provided with grooves 63 to permit the passage of fluid therearound, for lubricating purposes.

It is necessary to provide means automatically operable to unseat the valve 33 from the ports I! and 28, and move said valve to cover the ports I8 and I9, in order that fluid may then enter the chamber I6 by means of the port I I and move the impeller III in acounter-clockwise direction, as for example to the position illustrated at 64 in dotted lines in Fig. 14, forcing the fluid which entered the chamber I6 through the port I9 outwardly through the port 26.

As the preferred form for accomplishing the unseating of the valve 33, for example from the ports I] or 28, I secure to the upper end of the shaft Ill a collar 65, this collar being keyed to the shaft In by a key 66 and held against longitudinal displacement by lock nuts 61, the upper lock nut being pinned to the shaft II) as at 68. The collar 65 is provided with a pair of radially projecting knocker arms 69, 69. .It' will thus be appreciated that'the knocker arms 69 will be moved in unison with the shaft Ill and impeller I I I.

Therefore, as the impeller III moves toward the position 44 of Fig. 14, one of the knocker arms 69 will also be moved toward engagement with the upper end of the valve 33, as will be readily understood. Continued movement of the knocker arm 69 will result in the pivoting of the valve 33 on its pivot 34, and an unseating of the valve 33 0 from the cooperating seats on the ports I1 and 28. The impact and continued movement of the knocker arm 69, preferably in conjunction with additional means hereinafter described, swings the valve 33, to its opposite position, that is, with the face 4I engaging the seat 23 and with the face 42 engaging the seat 22, thus closing the ports I9 and I 8, and permitting the fluid to enter the chamber I6 by means of the port I1 and to be discharged therefrom, by the movement of the 7 impeller'III, through the port 23. As the impeller is moving in the reverse direction, the knocker arms-69 will likewise be moved in reverse direction, until the second knocker arm engages the upper end of the valve 33 and repeats the operation abovedescribed, but in a reverse direction, and this movement will continue, opening and closing alternate inlet and exhaust ports, as long as fluid under pressure is introduced into the barrel.

In order to insure shifting of the valve 33 from one set of inlet and exhaust ports to the opposite set of inlet and exhaust ports, and to prevent any stoppage of the valve 33 on dead center, I provide means. to cooperate with and assist the knocker arms 59. This mechanism comprises a socket member III located in the bottom of a recess 'II in the clutch block 45, and seated in said socket member is the lower end of a post I2, the upper end of said post being formed with a socket member I3 in, which seats the ball end I4 of a pin 15, this pin 15 having a shoulder or collar I6 formed thereon.

Slidable over the pin I5 is asleeved member 11 which I will hereinafter refer to as a spring arrow. The arrow IT has a shoulder or collar I8 formed thereon, the collars 15 and I8 forming abutments for a coiled spring I9. A ball end 88 is formed on the upper end of the arrow I1 and seats in a socket member 8I carried by the post 82 which is rockable in a recess '83 formed in the flared end 34 of the valve 33. v

Assuming that the motor is in the position illustrated in Fig. 19, with the valve 33 closing the ports. I I and 20. The fluid under pressure as it passes through the interior 9 of the barrel H will therefore enter the chamber I6 through the port I9, and will force the impeller III in a clockwise direction, exhausting the fluid in the chamber I5 through the outlet port I8. This movement of the impeller will likewise eifect a rotation of the shaft III and knocker arms 69. The

' clutch block 45 will also be rotated with the shaft III, carrying the socket member in a clockwise direction, or the left, as illustrated in Fig. 19, carrying the post "therewith. As the rotative movement of the clutch block 45 is continued, the elements 82, 11, I5 and I2 will become straightened, as a toggle, compressing the spring I5 between the collars I6 and I8.

After the aforementioned-members have passed their vertical position, the spring I8 willexpand, but still be held in compression. As the recess II reaches the extent of its stroke to the left, one knocker arm 59 is in engagement with the upper end of the valve 33. Meanwhile the spring I8 ence in the lengths of the two arms of the valve.

As the knocker arm ,58-continu'esto the left,

' Fig. 19, it will strike the upperend of. the valve 33 and unseat the same. The fluid pressure on the opposite sides of the valve now being equalized,

thespring arrow I'l will shoot away from the member 15, instantly pivoting the'valve 33 on its pivot 34 and seating the same against the seats of the ports I 5 and I8, and directing the fluid through the'inlet port Ifl. Thereuponthe fluid will enter the chamber I8 and effect a reverse movement of the impeller I I I, and this action will be repeated as, long as fluid under pressure is.

introduced through the barrel IL,

It will be understood and appreciated that as the impeller III is oscillating within its chamber I8, the shaft II and clutch block 45 are likewise oscillating, in turn transmitting this oscillation to the sleeve 50 and bit 5| carried thereby.

The torque developed by this motor is directly proportional to the exposed area of the impeller I I I, and this torque may be varied by varying the 5 length of theimpeller, as well of course as by varying the diameter of the chamber I8.

It will be apparent, from a glance at Fig. 19, that the inlet ports I1 and I9 are located a greater distance from the pivot 34 than are the 10 exhaust ports I8 and 20. This provides an increased leverage on the surfaces of the upper arm of the valve 33, which cooperates with the ports I8 and 28, and overcomes any tendency of fluid introduced into one side of the chamber I8 to unseat the valvefrom the exhaust port on the same side of said chamber.'

Each of the barrels II is provided with upper brackets H3 and lower brackets II4, connected to the respective upper and lower brackets H5 and IIS by links Ill and "8 which are pivoted at I I8 and'l28 respectively. A flexible fluid conducting hose I2I extends to each of the barrels II, the opposite end of each of these hoses communicating with a chamber I22 formed in a 25 bell I23.

The upper end portion of the barrel I is of relatively large'diameter and surrounds and has limited rotation about a shoulder portion of an inertia barrel 85, being swiveled thereto by a plug 86 threaded into the upper end of said barrel'l and resting on an antifriction bearing 81, which in turn is mounted on a shoulder-88 formed on said inertia barrel, relative rotative movement of the barrel I and they inertia barrel 85 being limited by a'pin I. (Figs. 5 and 13) projecting extending into a lost-motion recess 85 formed in the lower end of the inertia barrel.

A suitable fluid conducting hose I18 (Figs. 4 and 5) is connectedto the top of the inertia barrel 85, said hose "It being connected, at the ground surface, to a suitable pump to force fluid under pressure through the hose'. The barrel 85 and hose IIII are supported by cables 88 fixed in eyes on a collar 88, and the bell I23 is supported by cables 9! flxed in eyes in a collar 82, said collar 92 having a plug 93 threaded therein and the bell; I23 having a plug 34 threaded thereon, these plugs overlapping and having an anti-friction bearing 95 interposed-therebetween for free roso tata'bility of said bell.

" The inertia barrel is provided with ports I24 .(Fig. 5) so that fluid under pressure passing ducted through the hose I18 will be introduced 7odirectly through the main lead "I into the barrel I and to the fluid pressure motor contained therein.

The upper ends of the hoses I2I are flxed in a plug I25 threaded into the lower end of the bell H3. The bell I23 is provided with a plurality of brackets I26 having eyes I21, and a supporting cable I28 passes through each of the eyes I21 to rings or the like I29 fixed to each head I30 on the barrels II. v

It will thus be apparent that each of the individual barrels II is independently and flexibly supf m the barrels and I I.

- the collar 90, and extend upwardly as a single cable for ease of handling at the ground surface,

and the same is true of the cables BI, independent operating means for these cables being provided {at the ground surfaces. 1

The barrel I is provided with arms II39 and I40, and each of the barrels II is provided with arms MI and I42, these arms cooperating with the links I" and H8 respectively, as clearly illustrated in Fig. 4, to limit expansion of the barrels II relative to the barrel I, as will be hereinafter more fully explained.

Each of the bits 2 and GI is provided with fluid conducting passages I43 closely adjacent to the cutting edges thereo'f',--through which apertures I43 the fluid is forced after operating the motors This fluid effects a cooling action on the bits 2 and GI, and furthermore flushes the cuttings of said bits out of the bore I44 drilled by said bits. Said fluid is, of course, forced upwardly through the'bore I44, whence it passes to the usual slush pit, where the muddy fluid is allowed to settle and is again re-pumped through'the hose I10.

The bits 6| are located on a plane above the plane of the bit 2 and are so arranged that even in their expanded position their cutting area will overlap the cutting area of the bit 2, thus insuring complete drilling of t-hebore or shaft I44.

In Fig. 4 the device is illustrated in expanded position, and in Fig. the device is illustrated in contracted or collapsed position, this contraction being effected by raising the cable 89, which will draw the inertia barrel 85 upwardly, and, through the medium of the flange 88 and plug 85 will raise the barrel I upwardly until the upper end thereof contacts with the plug I25 in the bell I23.

This raising of the barrel I will also raise the and I40 and MI and I42 have engaged the upper and loweredges of the links II! and H8 respectively, as clearly illustrated in Fig, 4, thus'preventing further expansion or outward movement of the barrels I I relative to the barrel I.

Because of the expansible and contractile or collapsible feature of my novel assembly, I am enabled to case a shaft as it is bored, as clearly manner, as by bands I49 on the exterior thereof, and each section I45 is preferably constructed of segments I50 united, on their interior, by the straps I5I which may be welded or riveted thereto, or in any other desired manner. I45 preferably is provided with an outlet opening I45 so that the drilling fluid can flow therefrom to the slush pit although additional sections have been assembled or are being assembled above the opening I45 through which the drilling fluid at the moment is being discharged, so that discontinuance of the drilling operation is not necessary for the addition of casing sections.

In order to provide for a sufiiciently high amplitude of oscillation of the central bit 2 to pro- '15 vide cutting of the bit throughout the full circle without a large number of blades on the bit, and sufliciently large amplitude of oscillation for the planetary or out-rigger assembly to provide cutting of the out-rigger bits throughout the full circle about the central bit without a large number of out-rigger bits, I preferably employ for the central motor a motor of the type illustrated in my copending application Serial No. 271,923, flied April 21, 1928.

As is shown in Figs. 5 and 6 the lower portio of the inertia member 35 is of relatively small diameter and extends into the upper portion of the central motor casing I, its axial motive-fluid bore III communicating with the interior oi the casing through ports I II III (Fig. 6) and its exterior being rotatably sealed to the topof a belt (Fig. 5) formed on the upper end of the cas- Mounted in the casing and surrounding and 10- tatably sealed to the shaft 2I0 is a grease container 20I (Figs. 6 and 6) containing an annular piston 202 (Fig. 6) adapted to bear down upon a body of grease in the container, under the force of high-pressure drilling fluid entering the top of the container through apertures 203, 203 in its walls (Fig. 6) the portion of the container under the piston being in communication, through inlet apertures 204, 204, an axial bore 205, and outlet apertures 205, 200 in the shaft 2| 0, with the interior of a hollow-bit driving piston hereinafter to be described. The container is provided with an inlet 201 (Fig. 6") closed by a removable plug 208 for replenishment of the grease. a

Fixed in the casing I, below the grease container 20I and below a slide member 209 is an inner casing or cylinder 2I0, having vertical in-. let channels 2I9, and vertical discharge or exhaust chhhnels 220, Fig. 11; The inlet. channels 2I9 have upper and lower inlet ports 22I and 222 respectively leading to the interior of the in ner casing 2I0, and the discharge or exhaust channels 220 have the upper and lower discharge ports 223 and 224'respectively, leading from the interior oi the casing 2I3. The upper ends of the inlet channels 2I9 are open, as clearly illustrated in Fig. 11, but their lower ends are closed, and'the lower ends of the discharge channels 220 are open but their upper ends are closed.

Slidably fitted within the cylinder 2" are the valves or sleeves 225 and 223 of spider form'projecting from which are radial pins 221 and 223 respectively (Fig; 8) which work or slide in the vertical bearings 22! and 233 respectively. The pins 221 and 223 are connected by valve connecting rods 23I which work in the rod bearings 232 in the cylinder wallin order thatthe valves 22! and 223 will be compelled to move in'unison. The ports 22I and 224 (Figs. 8and 11) are some- Each section 5 posed and arranged that when one series of inlet ports are opened by their valve the series of discharge or exhaust ports at the same end of the cylinder will be closed by the said valve, and the reverse will be true of the corresponding series of inlet and discharge ports at the opposite end of the cylinder. Also, when one series of discharge ports are opened by their valve the inlet ports at the same end of the cylinder will be closed and the reverse will be true of the inlet and discharge ports at the other end of the cylinder. The upper and lower ends of the cylinder 2I8 have the respective plugs 233 and 234 threaded therein or otherwise attached thereto. The valve 225 has valve extensions or prongs 235 extending downwardly therefrom and the valve 226 has similar valve extensions or prongs 236 extending upwardly therefrom.

Splined within the cylinder 2I8 between said valves is a hollow piston 238 having a liner 239 therein and provided with the end stufling boxes 240 and MI forming hearings on the shaft 2|0.

The splining of the piston in the inner casing is effected by keys 251, 251 secured in the inner casing 2I8 and extended into vertical keyways 258, 258 (Fig. 6 in the piston 238. The piston 238 is adapted in being vertically reciprocated to J impart oscillations to the shaft 2|0, cam rollers 244, 244 running in helical cam grooves 243, 243 being mounted on the ends of a pin 245 which extends transversely through and projects from the shaft 2|0 and is fixed therein.

The above mentioned slide member 209 (Figs. 6 7 and 8) is secured to the upper ends of the rods 23I by screws 209 209 so that it is compelled to move up and down with the valves 225, 226, and it is formed with a. spider portion 209 defining passages 259, 259 for the motive fluid and with a slot 260 adapted at the end of the up stroke and at the end of the down stroke of the piston 238 to be at the position at which a roller 28I arrives at that time in the rotation of the shaft 2|0, so that during the down stroke of the piston the valve assembly including the slide member 209 is held in its elevated position by contact of the cam roller 2BI running on the underside of the spider member 209", as shown in Figs. 6 and 8, against the force of a helical compression spring 262 surrounding the shaft 2|0 and interposed between the piston and the lower valve 226 so as to urge the entire valve assembly downward, the cam roller 26I arriving at the slot 260 in the spider member 209 at the instant that the piston reaches the contact lugs 236 on the lower valve to initiate the movement of the valve, said spring then impelling the entire valve assembly quickly to its lowermost position and thereby reversing the valve arrangement for the return or up stroke of the piston, during which stroke the same roller 26I runs on the upper face of the spider portion 209 of the slide member 209, again registering with the slot 260 at the end of the up stroke of the piston and thus permitting the entire valve assembly to be elevated to its uppermost position by a helical compression spring 263 (Fig. 6 which surrounds the shaft 2|0 and is interposed between the piston and the spider portion of the'upper valve member 225, the piston engaging the contact lugs 235 of the upper valve member to initiate the upward movement of the valve assembly, the valve arrangement thus being reversed for the next downward stroke of the piston.

In the operation of the apparatus the motive fluid forced downward through the hose I10 in part passes through the central casing I to operate the motor therein for relative oscillation of the shaft 2|0 and the casing I, the motive fluid passing from thecasing I through the central. bit 2 to wash the cuttings to the top of the well. 5 Part of the motive fluid passes from the inertia member 85 through the channels I24 and hose conduits I2I (Fig. 5) and actuates the motors contained in the out-,rigger casings II to effect, relative oscillation between the said casings and their respective out-rigger bits 6|, the casings II being held by the link members II'8 against oscillation about their own axes but being compelled by said links to oscillate as a unit with the central casing I.

The shaft 2I0 is mounted in hearings in the plugs 233 and 234, and extends beneath the latter, said extended end being connected, by nut 246 and washer 241 (Fig. 6) to the chuck or drill collar 248. The upper end of this chuck within the casing I' is provided with inlet ports 249, and said chuck works between the bearing rings 250 and I and has an annular rib 252 which runs between the bearings 253 and 254, retained by said bearing rings, said rings being threaded into the 25 lower end of the casing I, as clearly illustrated in Fig. 6 The bit 2 is connected to the lower end of this chuck 248 in any desired manner, as by means of a tapered key 2 (Figs. 6 and 10.) This bit has channels 256 extending therethrough. Any suitable type of drill, bit or boring tool may be employed, the type depending on the character of the formation being drilled, but is constructed and arranged to effect an equal cutting action in either direction of oscillation.

If a shaft is being drilled or bored with my device, and the casing is following the drills in their descent, should it be desired to withdraw the machine for any purpose, raising the cables 89 will effect a contraction of the assembly until the greatest diameter of said assembly is less than the internal diameter of the casing I45, permitting withdrawal of the entire assembly upwardly through the casing. On replacing the device, it is lowered into the casing until the bits 2 and GI are below the shoe I48, whereupon the lifting strain on the cables 89 is relieved, and the device will automatically assume its expanded position, as illustrated in Fig. '2. The expansion of the planetary bits relative to the central bit may be halted at any suitable point, so that shafts or bores of varying diameters throughout their lengths may be drilled with a single machine.

Furthermore, by the use of my device, it is not necessary to drill a successively decreasing size of shaft, as has been heretofore necessary, the contractile feature of my device permitting the casing of the shaft with one diameter of casing to any desired depth.

The planetary fluid motors and their assemblies constitute a primary reaction and inertia structure such that as rotation is imparted to the bit 2, rotation in an opposite direction will be imparted to the barrel I and the assembly of bits 6|, which are secured against rotation with relation to the barrel I by the connecting links H8. If either the outrigger bit assembly or the central bit excessively resists rotation about the common center, the other will rotatefaster and farther than in normal operation until the projection I is stopped by the end wall of the lostmotion slot 85*, (Figs. 5 and 13) or until the projection 2| 0 is stopped by the end wall of the lostmotion slot 85 (Figs. 6 and 12), whereupon-the relatively free rotation of such member or structure will be resisted by the inertia of the barrel 85, which will compel rotation of the previously retarded member or structure.

Thus, while each of the bits BI is rotating about its own axis, said bits 6|," as a part of the inertia assembly, will be moved in an orbital path in the opposite direction about the bit 2, while rotating on their own axes, insuring complete and thorough drilling or boring of the entire shaft as the machine descends.

My novel machine will drill any size of shaft varying in diameter from the extreme contracted or collapsed position to the extreme expanded position.

It will be appreciated and understood that the number of bits 6| shown herein is for illustrative purposes only and that I am not confined to any particular number, but may utilize any number of bits required or desired.

When the load is released from the cables 89 to permit dropping of the barrel I, it will be appreciated that the load is then taken up by the cables 9|, each set of cables being of sufficient strength to support the entire assembly.

After a shaft is drilled according to my invention, the drilling machine is removed and the shaft is then pumped out in any desired manner, and lateral tunnels can be bored at any desired depths or levels.

Modifications are possible within the scope of my invention as defined in the appended claimsr connectedto an element of the said motor as to be oscillated about the axis of the central bit by the reaction force of the said motor, and bit means mounted on said bit-driving means.

3. Earth boring apparatus comprising a central bit, a motor of the oscillating type for driving said bit, bit-driving means so connected to an element of the said motor as to be oscillated about the axis of the central bit by the reaction force of the said motor, bit means mounted on said bit-driving means, and means for oscillating the said bit means about an axis other than that of the central bit.

4. Earth boring apparatus comprising a central bit, a motor of the oscillating type for driving said bit, bit-driving means so connected to an element of the said motor as to be oscillated about the axis of the central bit' by the reaction force of the said motor, bit means mounted on said bit-driving means, and an inertia member having lost-m0- tion connection to each of two relatively oscillating elements of the said motor for compelling each of the said elements to oscillate with relation to the formation'being bored.

5. Earth boring apparatus comprising a central bit, a set of planetary bits arranged about said central bit, and means for oscillating each of said bits on its own axis and for oscillating the planetary bits about the axis of the central bit.

6. Earth boring apparatus comprising a rotative central bit, a rotative planetary bit, and means for driving each of the said bits on its own axis and for driving the planetary bit about the central bit, said means comprising a pressure fluid motor adapted to discharge the motive fluid adjacent the bits for washing the cuttings to the top of the ground, the planetary bit being journaled on the motor casing assembly so as to be constrained to rotate therewith about the axis 5 type for driving said bit, the motor being adapted m to discharge the motive fluid adjacent the bit,

bit-driving means so connected to an element of the said motor as to sustain the reaction force of the motor, and bit means on said bit-driving means. 15

8. Earth boring apparatus comprising acentral bit, a pressure fluid motor of the oscillating type for driving said bit, bit driving means so connected to an element of saidmotor as to sustain the reaction force thereof, a planetary bit 20 mounted on said bit-driving means, a pressure fluid motor for driving said planetary bit on its own axis, and a conduit common to the two motors for supplying them with motive fluid.

9. Earth boring apparatus comprising a central 25 bit, a pressure. fluid motor of the oscillating type for driving said bit, bit drivingmeans so connected to an element of said motor as to sustain the reaction force thereof, a planetary bit mounted on said bit-driving means, a pressure fluid motor 30 for driving said planetary bit on its own axis, a conduit common to the two motors for supplying them with motive fluid, and an inertia member having lost-motion connection to each of two relatively oscillating elements of the motor of 35 the central bit for compelling each of the said elements to oscillate with relation to the formation being drilled.

10. In a well drilling machine of the kind described, a central bit, a plurality of bits circum- 40 ferentially arranged with respect to said central bit, means to effect movement of each of said bits about its axis, means to simultaneously effect movement of said circumferentially arranged bits in an orbit about said central bit, and means to 45 expand and contract said circumferentially arranged bits with respect to said central bit.

11. In a well drilling machine of the kind described, a central bit, a plurality of bits circumferentially arranged with respect to said central 5 bit, means to effect movement of each of said bits about its axis, means to simultaneously effect movement of said circumferentially arranged bits in an orbit about said central bit, means to expand and contract said circumferentially ar- 55 ranged bits with respect to said central bit, and means to limit the expansion and contraction of said circumferentially arranged bits.

12. In a well drilling machine of the kind described, a central barrel, a bit carried thereby, 0 means to effect movement of said barrel and bit about its axis, a plurality of barrels circumferentially arranged with respect to said central barrel, a bit carried by each of said outer barrels,

means to effect movement of each of said outer 5' about its axis, a plurality of barrels circumferentially arranged with respect to said central barrel, a bit'carried by each of said outer barrels,

means to effect movement of each of said outer bits about its axis, means including a plurality of pivoted links inter-connecting said'central.

barrel and said outer barrels to effect revolution of said outer bits about said central bit simulta-- links to draw said outer barrels toward said central bit or push said outer barrels away from said central barrel.

14. In a well drilling machine of the kind described, a central barrel, a bit carried thereby, means to efiect movement of said barrel and bit about its axis, a plurality of barrels circumferentially arranged with respect to said central barrel, a bit carried by each of said outer barrels, means to effect movement of each of said outer bits about its axis, means including a plurality of pivoted links inter-connecting said central barrel and said outer barrels to efiect revolution of [said outer bits about said central bit simultaneously with the axial movement thereof, means to move said central barrel longitudinally with respect to said outer barrels, longitudinal movement of said central barrel actuating said links to draw said outer barrels toward said central bit or push said outer barrels away from said central barrel, and means to limit the movement of said outer barrels toward or from said central barrel,

15. In a well drilling machine of the kind described, a central barrel, a bit carried thereby, means to effect movement of said barrel and bit about its axis, a plurality of barrels circumferentially arranged with respect to said central barrel, a bit carried by each of said outer barrels, meansto effect movement of each of said outer bits about its axis, means including a plurality of pivoted links inter-connecting said central barrel and said outer barrels to effect revolution of said outer bits about said central bit simultaneously with the axial movement thereof, means to move said central barrel longitudinally with respect to said outer barrels, longitudinal movement of said central barrel actuating said links to draw said outer barrels toward said central bit or push 'said outer barrels away from said central barrel, and-means adapted to engage said pivoted links to limit the movement of said outer barrels from said central barrel. I

16. In a well drilling machine of the kind described, a central barrel, a bit carried thereby, means to effect movement of said barrel and bit about its axis, a plurality of barrels circumferentially' arranged with'respect to said central barrel, a bit carried by each of said outer barrels, means to effect movement of each of said outer bits about its axis, means including a plurality of pivoted links inter-connecting said centra barrel and said outer barrels to efiect revolution of said 2 outer bits about said central bit simultaneously with the axial movement thereof, means to move said central barrel longitudinally with respect to said outer barrels longitudinalmovement of said central barrel actuating said-"links to draw said outer barrels towardsaid central bit or push said outer barrels away from said central barrel, and

, stop arms carried by said central barrel and said outer barrels adapted to engage the pivoted links to limit movement of said outer barrels from said central barrel.

CLYDE E. -BANNISTER. 

